FOXBOROUGH, Mass. — First it was Brandon Browner, a physical, lockdown cornerback. When he signed with the New England Patriots on March 15, fans rejoiced. Two days later, it was Darrelle Revis, considered by many (outside of Seattle anyway) to be the best cornerback in football.

When he signed with the Patriots, fans nearly became delirious.

Ten days later, defensive line stalwart Vince Wilfork, who had threatened to take his girth and talent elsewhere, re-upped with the Patriots. More good news for a defense that has never been confused with the Monsters of the Midway, Steel Curtain, Doomsday Defense or Fearsome Foursome.

Wilfork, coming off an Achilles injury that cost him the last 12 games of the 2013 season, was back at training camp Thursday on the fields behind Gillette Stadium. So was Jerod Mayo, who tore a pectoral muscle two weeks after Wilfork went down and didn’t play again in 2013.

The additions of Revis and Browner and the return of Wilfork and Mayo – along with Tommy Kelly, the mammoth defensive tackle who missed the last 11 games of the 2013 season with a knee injury (and still hasn’t been cleared to practice) – have Patriots fans giddy over the team’s defense this year.

On paper, the Patriots will have one of the best secondaries in the game. On paper, the Patriots front seven will be difficult to run against. On paper, this defense could be special.

Fans know this. The Patriots know this. And that’s why … they … want … you … to … slow … down.

The Patriots are thrilled that everyone is excited about the defense. There’s just a lot of work to be done yet.

“Our goal always is to put the best team on the field, and that’s what we’re going to do,” said Wilfork, who participated in most drills on Thursday. “I don’t care how we look on film, how we look on paper, you have to be able to put it together on the field. And the stepping stone for that is now, is camp. You can’t look at last year, you can’t predict the future, you can only go about now … So we have a long way to go.

“I’m not going to sit here and say how great we’re going to be or how this person looked. It’s a building process and right now we’re in that building mode.”

There is no question that Browner – who must sit out the first four games in an NFL-mandated suspension for violating the league’s substance abuse policy – and Revis change everything about the Patriots defense. Their ability to shut down the opposition’s top receivers will allow the pass rush an extra second or two to get to the quarterback. Their ability to cover someone 1-on-1 will allow other players to make plays. They will force teams to try to run the ball into New England’s middle, which should be boosted by the return of Wilfork, Mayo and Kelly.

“We’ve got some of our guys back,” said defensive end Rob Ninkovich. “Last year it was tough when we lost Mayo and Vince and Tommy. Those were big blows. So, having those guys next to you definitely gives you more confidence.”

But players and coaches are cautioning people that a lot of work is yet to be done. New faces don’t necessarily translate into new success.

“There are personnel changes for us every year,” said Matt Patricia, the Patriots defensive coordinator. “For us, we’re just focused on today, trying to get better, trying to come out and improve, see if what we did in the classroom can translate onto the field, seeing how it worked against our offense.”

Duron Harmon, a second-year safety expected by many to be the fourth starter in the secondary alongside Devin McCourty, said he tends to be very quiet around Revis and Browner.

“They gave me some pointers,” he said. “Those guys are really good players so when I’m around them, I try to do more listening than talking.”

Harmon, who had an uneven rookie season, feels much more comfortable this year, partly because of the experience he gained last year – “Good and bad,” he said – and partly because of the presence of Revis and Browner.

“You know what they can do, you know what risks you can take, you know how to play different things, you know exactly what they’re going to do,” he said. “And the main thing that comes into play is to build in relationships and make a strong connection on the field with both so we can be on the same page.

“There’s a lot of communication going on. In the meeting room we have to talk, to see, ‘All right, this play, what you going to do right here if we do this?’ And it’s not only for football, but allows us to get closer as a team.”

Revis’ presence helps more than just the defense, as Tom Brady said on Thursday after practice.

“He challenges us, he challenges the receivers, and it’s nice to go against someone like that,” said Brady. “We’ve had great corners here in the past, but he’s a great competitor. Having the chance to compete against him on another team, I certainly appreciate having him on our team.”

Someone asked Wilfork about the track records of the new guys coming to the team, including defensive end Will Smith in the conversation.

Wilfork said none of that mattered anymore. They may have been effective players elsewhere, they may have even been All Pros, but this is a new year.

“It’s the start of camp,’’ said Wilfork. “You know about everyone we have on the team, but at the same time we got to put it all together. That what camp is for, to build a team.”

One day at a time.